Electrical vehicle charging stations or Electrical Vehicle Supply Equipment (EVSE) are used to supply electric vehicles (EVs) with electrical energy. Modern EVSEs are equipped with technology that allows them to communicate with electric vehicles to control the charging rate. This capability allows the charging station to communicate the amount of charging capacity available to the EV. The EV, in turns, selects a charging capacity based on the available charging capacity. The selection is typically based on the criterion to charge the EV battery as fast as possible.
However, in many cases it is not necessary for the EV to charge the battery at the full rate. For example, EV drivers may drive their car to work and leave it plugged in all day, even though charging completes in only a few hours. Similarly, when drivers arrive home at night they often leave vehicles plugged in overnight, as the car is required to be charged by the next morning.